1. Field of the Invention
The present invention relates to an optical detecting device, and more particularly, to an optical detecting device capable of tracing a light emitting timing sequence of an active reference light source and a related method of synchronization adjustment.
2. Description of the Prior Art
For eliminating effect of background noise, a conventional optical detecting device utilizes a reference light source with specific light emitting frequency to filter the background noise. The light emitting frequency of the reference light source is varied due to low energy of the built-in battery. Two conventional detection methods, such as synchronous flickering detection and asynchronous flickering detection, can be applied to the image detector for accurately acquiring the reference light source with the specific light emitting frequency. The conventional detection methods are set according to comparison between the exposure timing sequence of the image detector and the light emitting timing sequence of the reference light source. The conventional synchronous flickering detection method utilizes the optical detecting device to output a signal, and the signal is received by a receiver of the reference light source. The light emitting timing sequence of the reference light source is adjusted according to the signal receiving time, so as to synchronize with the exposure timing sequence of the image detector. However, the reference light source includes the extra signal receiver, and has drawbacks of expensive cost.